##  [Knudson's Two-Hit Hypothesis](/index.php/knudsons-two-hit-hypothesis) 

  ##  [Knudson's Two-Hit Hypothesis](https://health.quantumdictionary.io/knudsons-two-hit-hypothesis-0) 

  

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**Health & Life Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A genetic model proposing that tumorigenesis involving classical tumor suppressor genes requires inactivation of both alleles in a given cell through two successive 'hits' (mutations, deletions, or equivalent inactivating events), with hereditary forms explained by a germline first hit that reduces the number of somatic events needed.